Thomas goodenough



(NoModeL) I T. GOODENOUGH.

PNEUMATIC DOOB. CHECK.

No; 89 ,429. Patent ed Nov. 27, 188

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UNITED STATES PATENT OFFICE.

THOMAS GOODENOUGH, OF WVOODSIDE, ASSIGNOR TO THE AKBAR MANU- FAGTURING COMPANY, OF NEW YORK, N. Y.

PNEUMATIC DOOR-CHECK.

SPECIFICATION forming pan: of Letters Patent No. 393,429, dated November 27, 1888.

Application filed May 4, 1888.

T aZZ whom it may concern.-

Be it known that I, THOMAS GOODENOUGH, of WVoodsidc, Queens county, New York, have invented a certain new and useful Improvement in Door Checks, of which the following is a specification.

I will describe my improvement in detail and then point out the novel features in the claims.

[O In the accompanying drawings, Figure l is a face view ofadoor check embodying my improvement applied to a door, the door being closed. Fig. 2 is a plan or top view of the same the door being open. Fig. 3isaface view of the door-check, a portion of the outer shell or case being broken away to disclose the interior, and looking upwardly from Fig. 1. Fig. 4 is an enlarged view in section ofa certain vent employed.

Similar letters of reference designate corresponding parts in all the figures. A designates a case or shell. shell may be cast in one piece. It comprises two cylindrical portions, a a. Cappieces a having a screw-threaded. connection with the ends ofthe caseorshell,may beemployed to close the outer ends of the cylinders. In the example of my improvement shown the cylindrical portion a islonger than the portion a. Within the cylindrical portion a is arranged a coilspring, B, which abuts at one end against the cappiece a at the outer end of the portion a and at the other against a plate, (1?. The plate a has rigidly secured to it at about its center one end of a rack, C. The rack O and plate a? constitute a plunger. The rack O is of sufficient length to extend into the cylindrical portion a of the shell. Upon its end within the portion a is secured a piston, D. This piston may be provided with any suitable packing to secure an air-tightjoint. The portion a constitutes a pneumatic cylinder.

When a door having my check applied to it is opened, the spring B is compressed and the piston D is withdrawn, air being admitted freely to cylindrical portion a inward of the piston. These operations are accomplished as follows:

F designates a pinion mounted upon a shaft, 50 f, having suitable bearings in a portion of the case or shell A, intermediate of the cylin- This case or Serial No. 272,774. (No model.)

drical portions a a. The pinion F gears with the rack C. One end of the shaftfextends beyond the case or shell A and has secured to it one end ofa lever, G. This lever is provided with a longitudinally-extending slot, 9, having closed ends.

J designates a pin or projection extending into the slotg in the lever. This pin or projection forms part of a bracket, which bracket is secured to the door by screws or otherwise.

It is advantageous to form the bracket in two sections,jj', adapted to slide one upon the other, but yet so engaged as not to be liable to lateral displacement. The sectionsjj are provided with longitudinal slots, through which extends a clampingscrew, 9, whereby the partsjj may be secured in any position into which they may be adjusted in a well-known manner. This admit-s of accommodating the device to doors having different depths of door-frame.

It will be readily seen that when the door is opened the lever G will move along on the pin or projection J, thus causing a rotation of the shaft f, and consequently of the pinion F, whereby the rack G will be moved in a direction to compress the spring B. When the door is released, the spring operates to cause a reverse movement of the parts and a consequent 8c closing of the door. The check is,however, sloweclosing.

As previously stated,when the door is being opened air is admitted freely to thepneurnatic cylinder. Thechiefresistancethereforeoffered to the opening of the door is that of the spring B. The resistance offered to the closing ofthe door is,on the contrary,that of an air-cushion formed in the pneumatic cylinder. This aircushion is destroyed very slowly, so that the door may close gently and without slamming.

In effecting this operation I employ a vent of peculiar construction, (shown more clearly in Fig. 4,) in which H designates a valve. From the valve H extends a spindle, h, which acts as a guide to the movement of the valve. The valve in this example of my improvement is arranged in a valve-chamber, h, formed by a hollow metal piece, if, which is open at its inner end, and is provided with a stop-pin, h",

near its inner end to prevent the valve from passing out of the chamber. The metal piece it is screw-tln'eaded externally, and engages a tapped hole, It", in the cap aflwherebyitis re tained in place. The outer portion of the metal piece If is enlarged in the example of my improvement shown into the form ofa bolt-head, If. The valve seat 7r for the valve H is within the bolt head. The spindle It plays loosely throrgh an aperture, h, extending about centrally through the bolt-head 71 Between the bolt-head Z1? and the cap a is.a washer, h", which may be of leather. The screwthreaded portion ot' the metal piece h engages sotnewhat loosely with the tapped hole h. \Vhen the door is being opened and the piston D withdrawn, the valve H is drawn backwardly by the pressure of air from the outside, and air enters the pneumatic cylinder freely through the aperture h in the bolt-head h When the door is being closed and the piston is being returned,the pressure of air from within immediately forces the valve 11 to its seat. An air-cushion is then formed between the piston D and the cap'a which is only destroyed by the slow passage of air outwardly between the screw-threaded portion ot the metal piece It and the wall of the tapped hole It, and be tween the washer 717 and, the cap a The rapidity with which the door will close may be regulated as desired by merely rotating the metal piece h to increase or decrease the pressure which shall be exerted by the bolthead it upon the washer It.

The case or shell A may be mounted upon a base-plate, J, to which it may be secured by screws '17, passing through holes in lugs i? on the case or shell.

The shaft f may be made to extend upon either side of the case or shell in order to accommodate right and left handed doors.

The check will usually be mounted on the door-casing and the pin or projection J on the door; but of course these positions might be reversed,

I do not mean to limit myself to the precise details of construction herein set forth, as it is obvious that a workman might alter the same and yet employ my invention. For instance, for the pinion and rack shown might be sub stitnt'ed other devices in operative engagement which would readily suggest themselves to the mind of a mechanic without departing from the spirit of my invention.

\Vhat I claim as my invention, and desire to secure by Letters Patent, is-

1. In a door check, the combination,with a pneumatic cylinder, of a spring arranged beyond the portion of the cylinder traveled by the piston ot' such cylinder, a connection between the piston rod and the spring, a lever for operating the piston and spring in operative engagement with the piston-rod intermediate ot the spring and the piston, and a vent on the pneumatic cylinder, the whole being adapted to be arranged upon a door and door-casing, one of which is provided with a pin or projection having a sliding connection with the lever, substantially as specified.

2. in a door-cheek, the combination, with a case or shell comprising a pneumaticcylinder, of a piston, a rack connected to the piston, a spring opposing the movement of the piston in one direction and moving the piston in the other direction, a pinion engaging said rack, a lever for operating the pinion, and a vent on the pneumatic cylinder, the whole being adapted to be arranged on a door and doorcasing, one of which is provided with a pin or projection having a connection with said lever, substantially as specified.

T1 t0 MA (l 00D IGNOl It'll t'.

Witnesses:

(humans 0. Ken r, En'wnv ll. BROWN. 

